Linear regression

In the following section, we performed traditional linear regression with equation \[Y = \beta_0 + \beta_1 *X\] where \(Y\) is one of the epigenetic age accelerations, and \(X\) is one of the ambient exposure measurements or the urinary measurements.

The estimations of \(\beta_1\) with given \(Y\) and \(X\) are shown below, which can be interpreted as “the mean of Y changes given a one-unit increase in X while holding other variables constant”.

Ambient Exposure

## X: Ambient Exposure Measurements:
##                                                  bap               pm25
## Horvath EAA                       -0.0068   (0.0048) 0.0018    (0.0024)
## Hannum EAA                        -0.0019   (0.0042) 0.0001    (0.002 )
## PhenoAge EAA                      -0.0031   (0.0046) -0.0013   (0.0022)
## Skin&Blood EAA                    0.0028    (0.0034) -0.0006   (0.0017)
## GrimAge EAA                       0.0017    (0.0031) 0.0013    (0.0015)
## DNAmTL                            0         (0.0002) -0.0001   (0.0001)
## IEAA                              -0.0097*  (0.0042) 0.0015    (0.0022)
## EEAA                              -0.0004   (0.0054) 0.0005    (0.0026)
##                [P<0.001: ***; P<0.01: **; P<0.05: *]               <NA>
##                               ANY                BPE                BaA
## Horvath EAA    0.0009 ** (0.0003) -0.007    (0.0046) -0.0041   (0.0029)
## Hannum EAA     0.0004    (0.0003) -0.0026   (0.004 ) -0.0012   (0.0025)
## PhenoAge EAA   0.0005 *  (0.0003) -0.005    (0.0043) -0.0009   (0.0027)
## Skin&Blood EAA 0.0004    (0.0002) 0.0026    (0.0032) 0.0013    (0.0021)
## GrimAge EAA    0.0007 ***(0.0002) 0.0014    (0.003 ) 0.0014    (0.0019)
## DNAmTL         0         (0     ) 0         (0.0002) 0         (0.0001)
## IEAA           0.0006 *  (0.0003) -0.0101*  (0.004 ) -0.0054*  (0.0026)
## EEAA           0.0006    (0.0003) -0.0013   (0.0051) -0.0003   (0.0032)
##                              <NA>               <NA>               <NA>
##                               BbF                BkF                CHR
## Horvath EAA    -0.0033   (0.0029) -0.0192   (0.0133) -0.0033   (0.0032)
## Hannum EAA     -0.0015   (0.0026) -0.0069   (0.0116) -0.0015   (0.0028)
## PhenoAge EAA   -0.0015   (0.0028) -0.0093   (0.0125) -0.0007   (0.003 )
## Skin&Blood EAA 0.0013    (0.0021) 0.0061    (0.0094) 0.0013    (0.0022)
## GrimAge EAA    0.0013    (0.0019) 0.006     (0.0086) 0.0019    (0.002 )
## DNAmTL         0         (0.0001) 0.0001    (0.0005) 0         (0.0001)
## IEAA           -0.0048   (0.0026) -0.0266*  (0.0116) -0.0047   (0.0028)
## EEAA           -0.0006   (0.0033) -0.0025   (0.0147) -0.0004   (0.0035)
##                              <NA>               <NA>               <NA>
##                               DBA                FLT                FLU
## Horvath EAA    -0.0186   (0.0117) -0.006    (0.0031) 0.0008    (0.0008)
## Hannum EAA     -0.0085   (0.0102) -0.0023   (0.0027) -0.0003   (0.0007)
## PhenoAge EAA   -0.0082   (0.011 ) -0.0013   (0.0029) 0.0006    (0.0007)
## Skin&Blood EAA 0.0044    (0.0083) -0.0003   (0.0022) 0.0005    (0.0006)
## GrimAge EAA    0.0048    (0.0076) 0.0012    (0.002 ) 0.0009    (0.0005)
## DNAmTL         -0.0001   (0.0005) 0.0001    (0.0001) 0         (0     )
## IEAA           -0.0262*  (0.0102) -0.0064*  (0.0027) 0.0006    (0.0007)
## EEAA           -0.0047   (0.013 ) -0.0021   (0.0034) -0.0001   (0.0009)
##                              <NA>               <NA>               <NA>
##                               IPY                NAP                PHE
## Horvath EAA    -0.0107   (0.0082) 0.0002 ** (0.0001) 0.0006    (0.0005)
## Hannum EAA     -0.0019   (0.0072) 0.0001    (0.0001) -0.0001   (0.0004)
## PhenoAge EAA   -0.008    (0.0077) 0.0001 *  (0.0001) 0.0004    (0.0005)
## Skin&Blood EAA 0.0055    (0.0058) 0.0001    (0     ) 0.0003    (0.0004)
## GrimAge EAA    0.0042    (0.0053) 0.0001 ***(0     ) 0.0006 *  (0.0003)
## DNAmTL         0.0001    (0.0003) 0         (0     ) 0         (0     )
## IEAA           -0.017 *  (0.0072) 0.0001 *  (0.0001) 0.0005    (0.0004)
## EEAA           -0.0002   (0.0091) 0.0001    (0.0001) 0         (0.0006)
##                              <NA>               <NA>               <NA>
##                               PYR
## Horvath EAA    -0.0054   (0.003 )
## Hannum EAA     -0.0018   (0.0026)
## PhenoAge EAA   -0.001    (0.0028)
## Skin&Blood EAA 0.0002    (0.0021)
## GrimAge EAA    0.0012    (0.0019)
## DNAmTL         0.0001    (0.0001)
## IEAA           -0.006 *  (0.0026)
## EEAA           -0.0015   (0.0033)
##                              <NA>

Urinary Measurements

## X: Urinary Measurements:
##                              Benzanthracene_Chrysene        Naphthalene
## Horvath EAA                       -0.0347   (0.1329) -0.0015*  (0.0006)
## Hannum EAA                        0.0524    (0.1142) -0.0012*  (0.0005)
## PhenoAge EAA                      -0.0577   (0.1229) -0.0011   (0.0006)
## Skin&Blood EAA                    0.0831    (0.0963) -0.0015***(0.0004)
## GrimAge EAA                       0.1139    (0.0848) 0         (0.0004)
## DNAmTL                            -0.0044   (0.005 ) 0         (0     )
## IEAA                              -0.1061   (0.1218) -0.001    (0.0005)
## EEAA                              0.1062    (0.1448) -0.0012   (0.0007)
##                [P<0.001: ***; P<0.01: **; P<0.05: *]               <NA>
##                2.Methylnaphthalene 1.Methylnaphthalene       Acenaphthene
## Horvath EAA     -0.0076   (0.0072)  -0.0107   (0.0175) 0.0222    (0.0388)
## Hannum EAA      -0.0041   (0.0063)  -0.0195   (0.0149) 0.0364    (0.0331)
## PhenoAge EAA    -0.009    (0.0067)  -0.0197   (0.016 ) 0.0871 *  (0.0352)
## Skin&Blood EAA  -0.0073   (0.0053)  -0.0248   (0.0126) -0.0153   (0.0283)
## GrimAge EAA     0.0074    (0.0047)  0.0115    (0.0112) 0.0632 *  (0.0242)
## DNAmTL          -0.0003   (0.0003)  -0.0006   (0.0007) -0.0012   (0.0015)
## IEAA            -0.0049   (0.0067)  -0.0035   (0.016 ) 0.0423    (0.0354)
## EEAA            -0.0027   (0.0079)  -0.0178   (0.019 ) 0.0437    (0.0421)
##                               <NA>                <NA>               <NA>
##                Phenanthrene_Anthracene       Fluoranthene             Pyrene
## Horvath EAA         0.0032 *  (0.0015) 0.0313    (0.0176) 0.0604    (0.8089)
## Hannum EAA          0         (0.0013) 0.0014    (0.0152) 0.4964    (0.6998)
## PhenoAge EAA        0.0016    (0.0014) 0.0186    (0.0164) 1.1837    (0.7204)
## Skin&Blood EAA      0.0003    (0.0011) 0.0075    (0.013 ) 0.4335    (0.5651)
## GrimAge EAA         0.003  ** (0.0009) 0.0336 ** (0.011 ) 0.8996    (0.5026)
## DNAmTL              -0.0002** (0.0001) -0.002 ** (0.0007) -0.0247   (0.0307)
## IEAA                0.0027    (0.0014) 0.0253    (0.0161) 0.3588    (0.7359)
## EEAA                0.0005    (0.0016) 0.0066    (0.0194) 0.7558    (0.8847)
##                                   <NA>               <NA>               <NA>

Current fuel type

In the following section, we performed traditional linear regression with equation \[Y = \beta_0 + \beta_1 * I(\text{Smokeles}) + \beta_2 * I(\text{Smoky}) + \beta_3 * I(\text{Wood_and_or_Plant})\] where \(Y\) is one of the epigenetic age accelerations and the reference as the gas/electricity fuel type from the control group.

The estimations of \(\beta_0\), \(\beta_1\), \(\beta_2\), \(\beta_3\), \(\beta_4\) with given \(Y\) are shown below, which can be interpreted as “the expected change of Y if switching form the gas/electricity fuel type to the given fuel type, while holding other variables constant”.

The numbers of observations with each current fuel type:

## 
##         Gas/Elect          Smokeles             Smoky Wood_and_or_Plant 
##                12                17                87                 8

Childhood Exposure: Birth Fuel Type

In the following section, we performed traditional linear regression with equation \[Y = \beta_0 + \beta_1 * I(Smokeles) + \beta_2 * I(Smoky) + \beta_3 * I(Wood) + \beta_4 * I(Mix)\] where \(Y\) is one of the epigenetic age accelerations and the reference as the gas/electricity fuel type from the control group.

The estimations of \(\beta_0\), \(\beta_1\), \(\beta_2\), \(\beta_3\), and \(\beta_4\) with given \(Y\) are shown below, which can be interpreted as “the expected change of Y if switching form the gas/electricity fuel type to the given fuel type, while holding other variables constant”.

The numbers of observations with each current fuel type:

## 
## Gas/Elect       Mix  Smokeles     Smoky      Wood 
##        12        53         5        47        11

Lifetime Exposure: Cumulative Fuel Type

In the following section, we performed traditional linear regression with equation \[Y = \beta_0 + \beta_1 * I(Smoky) + \beta_2 * I(Mix)\] where \(Y\) is one of the epigenetic age accelerations and the reference as the gas/electricity fuel type from the control group.

The estimations of \(\beta_0\), \(\beta_1\), and \(\beta_2\) with given \(Y\) are shown below, which can be interpreted as “the expected change of Y if switching form the gas/electricity fuel type to the given fuel type, while holding other variables constant”.

The numbers of observations with each cumulative fuel type:

## 
## Gas/Elect       Mix     Smoky 
##        12        82        37

Current Stove Type

## 
## Firepit_and_unventilated                Gas/Elect                      Mix 
##                       22                       12                       19 
##           Portable_stove               Ventilated 
##                       20                       51

In the following section, we performed traditional linear regression with equation \[Y = \beta_0 + \beta_1 * I(\text{Portable_stove}) + \beta_2 * I(\text{Ventilated}) + \beta_3 * I(\text{Firepit_and_unventilated}) + \beta_4 * I(\text{Mix})\] where \(Y\) is one of the epigenetic age accelerations and the baseline as the Gas/Elect stove type from the control group.

The estimations of \(\beta_0\), \(\beta_1\), \(\beta_2\), \(\beta_3\), and \(\beta_4\) with given \(Y\) are shown below, which can be interpreted as “the expected change of Y if switching form the Gas/Electricity stove type to the given stove type, while holding other variables constant”.

Linear regression with log transformation

In the following section, we performed traditional regression with equation \[Y = \beta_0 + \beta_1 *log(x)\] where \(Y\) is one of the epigenetic age accelerations, and \(X\) is one of the ambient exposure measurements or the urinary measurements.

The estimations of \(\beta_1\) with given \(Y\) and \(log(X)\) are shown below, which can be interpreted as “the mean of Y changes given a one-unit increase in log(X) while holding other variables constant”.

Ambient Exposure

## X: Ambient Exposure Measurements:
##                                                  bap               pm25
## Horvath EAA                       -0.1076   (0.3766) 0.4429    (0.5902)
## Hannum EAA                        -0.2152   (0.3272) -0.1099   (0.507 )
## PhenoAge EAA                      -0.3256   (0.3523) -0.0291   (0.5488)
## Skin&Blood EAA                    0.4187    (0.263 ) -0.0782   (0.4314)
## GrimAge EAA                       0.12      (0.2417) 0.4732    (0.3763)
## DNAmTL                            -0.0021   (0.0145) -0.0225   (0.0225)
## IEAA                              -0.5106   (0.3316) 0.1967    (0.5418)
## EEAA                              -0.0601   (0.4147) 0.0686    (0.6445)
##                [P<0.001: ***; P<0.01: **; P<0.05: *]               <NA>
##                               ANY                BPE                BaA
## Horvath EAA    0.7994    (0.4907) -0.0795   (0.3582) -0.0251   (0.3096)
## Hannum EAA     0.3506    (0.4299) -0.2021   (0.3111) -0.1897   (0.2688)
## PhenoAge EAA   0.6353    (0.4466) -0.3914   (0.3343) -0.2167   (0.2899)
## Skin&Blood EAA 0.587     (0.3403) 0.4958 *  (0.2487) 0.2756    (0.217 )
## GrimAge EAA    0.5797    (0.2971) 0.1416    (0.2298) 0.0942    (0.1987)
## DNAmTL         -0.0032   (0.0178) -0.0053   (0.0138) -0.0013   (0.0119)
## IEAA           0.5578    (0.4315) -0.4463   (0.3159) -0.3353   (0.2735)
## EEAA           0.4099    (0.5422) -0.0977   (0.3943) -0.0628   (0.3408)
##                              <NA>               <NA>               <NA>
##                               BbF                BkF                CHR
## Horvath EAA    0.0666    (0.3955) -0.092    (0.3903) 0.0732    (0.3155)
## Hannum EAA     -0.0909   (0.344 ) -0.1946   (0.3391) -0.1423   (0.2742)
## PhenoAge EAA   -0.3042   (0.3702) -0.2683   (0.3655) -0.2478   (0.2953)
## Skin&Blood EAA 0.4133    (0.2765) 0.4052    (0.2729) 0.2033    (0.2218)
## GrimAge EAA    0.0817    (0.254 ) 0.1449    (0.2504) 0.066     (0.2026)
## DNAmTL         0.0002    (0.0152) -0.0003   (0.015 ) 0.0011    (0.0121)
## IEAA           -0.3291   (0.3503) -0.4921   (0.3441) -0.25     (0.2796)
## EEAA           0.033     (0.4355) -0.0244   (0.4298) -0.0267   (0.3474)
##                              <NA>               <NA>               <NA>
##                               DBA                FLT                FLU
## Horvath EAA    -0.1919   (0.3165) -0.1098   (0.2381) 0.9256    (0.5483)
## Hannum EAA     -0.1881   (0.2753) -0.1805   (0.2067) 0.0906    (0.4827)
## PhenoAge EAA   -0.1555   (0.2971) -0.171    (0.2231) 0.4042    (0.5035)
## Skin&Blood EAA 0.27      (0.2223) 0.1043    (0.1678) 0.5336    (0.3829)
## GrimAge EAA    0.1159    (0.2034) 0.0775    (0.1529) 0.4703    (0.3359)
## DNAmTL         -0.0105   (0.0121) 0.001     (0.0092) -0.006    (0.0199)
## IEAA           -0.5038   (0.278 ) -0.2984   (0.2101) 0.6214    (0.4828)
## EEAA           -0.0711   (0.349 ) -0.0818   (0.2623) 0.1179    (0.6085)
##                              <NA>               <NA>               <NA>
##                               IPY                NAP                PHE
## Horvath EAA    -0.2733   (0.3977) 1.3359 *  (0.5622) 0.9582    (0.5159)
## Hannum EAA     -0.2651   (0.3458) 0.5956    (0.4986) 0.1196    (0.4556)
## PhenoAge EAA   -0.3284   (0.3727) 0.9013    (0.5172) 0.5163    (0.4738)
## Skin&Blood EAA 0.407     (0.2786) 0.9097 *  (0.3911) 0.519     (0.3612)
## GrimAge EAA    0.1506    (0.2556) 0.7901 *  (0.3433) 0.5162    (0.3158)
## DNAmTL         -0.0069   (0.0153) -0.0069   (0.0207) -0.0033   (0.0188)
## IEAA           -0.6474   (0.3493) 0.9301    (0.4975) 0.6943    (0.454 )
## EEAA           -0.166    (0.4384) 0.7714    (0.6282) 0.1681    (0.5742)
##                              <NA>               <NA>               <NA>
##                               PYR
## Horvath EAA    -0.0925   (0.24  )
## Hannum EAA     -0.1644   (0.2084)
## PhenoAge EAA   -0.1787   (0.2248)
## Skin&Blood EAA 0.1355    (0.169 )
## GrimAge EAA    0.0627    (0.1542)
## DNAmTL         -0.0001   (0.0092)
## IEAA           -0.306    (0.2117)
## EEAA           -0.0564   (0.2644)
##                              <NA>

Urinary Measurements

## X: Urine Measurements:
##                              Benzanthracene_Chrysene        Naphthalene
## Horvath EAA                       0.4364    (0.4199) -0.1112   (0.5242)
## Hannum EAA                        0.0504    (0.3625) -0.041    (0.4494)
## PhenoAge EAA                      -0.235    (0.3897) -0.1722   (0.4862)
## Skin&Blood EAA                    0.1857    (0.306 ) -0.2724   (0.3817)
## GrimAge EAA                       0.3483    (0.2691) 0.4953    (0.3327)
## DNAmTL                            -0.0194   (0.0159) -0.0152   (0.02  )
## IEAA                              -0.1814   (0.3873) 0.1021    (0.4804)
## EEAA                              0.2666    (0.4597) 0.0638    (0.5713)
##                [P<0.001: ***; P<0.01: **; P<0.05: *]               <NA>
##                2.Methylnaphthalene 1.Methylnaphthalene       Acenaphthene
## Horvath EAA     0.1993    (0.5128)  0.0692    (0.4838) 0.2138    (0.4341)
## Hannum EAA      0.36      (0.4455)  0.1215    (0.4129) 0.4444    (0.3704)
## PhenoAge EAA    -0.0367   (0.4763)  -0.1028   (0.4451) 0.9413 *  (0.3944)
## Skin&Blood EAA  -0.1199   (0.3799)  -0.2512   (0.3518) -0.172    (0.3166)
## GrimAge EAA     0.7028 *  (0.3315)  0.3109    (0.308 ) 0.6184 *  (0.2727)
## DNAmTL          -0.0342   (0.0194)  -0.0115   (0.0184) -0.0141   (0.0165)
## IEAA            0.1031    (0.4729)  -0.1805   (0.441 ) 0.3237    (0.3972)
## EEAA            0.5612    (0.5589)  0.3686    (0.5256) 0.6301    (0.4702)
##                               <NA>                <NA>               <NA>
##                Phenanthrene_Anthracene       Fluoranthene             Pyrene
## Horvath EAA         0.8824 *  (0.3813) 0.5725    (0.4641) 0.307     (0.7555)
## Hannum EAA          0.2718    (0.3329) 0.1574    (0.4   ) 0.2786    (0.655 )
## PhenoAge EAA        0.5222    (0.3582) 0.5958    (0.4299) 0.6001    (0.6792)
## Skin&Blood EAA      0.1645    (0.2836) -0.0413   (0.3405) 0.6492    (0.5259)
## GrimAge EAA         0.5446 *  (0.2445) 0.6226 *  (0.2937) 0.5533    (0.4736)
## DNAmTL              -0.0413** (0.0144) -0.0394*  (0.0175) -0.027    (0.0286)
## IEAA                0.5602    (0.3533) 0.2816    (0.4271) 0.5419    (0.6865)
## EEAA                0.4976    (0.4219) 0.245     (0.5082) 0.5302    (0.828 )
##                                   <NA>               <NA>               <NA>